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Astronomy

Using Ground-Penetrating Radar to Find Subglacial Lakes on Mars

Quick fact

In 2018, scientists using the MARSIS radar on the Mars Express orbiter detected a 20-kilometer-wide lake of liquid water buried 1.5 kilometers beneath the south polar ice cap.

Why this is interesting

There might be hidden lakes of liquid water beneath the Martian ice caps. How can we see them from orbit millions of kilometers away?